python37Packages.typing-extensions: 3.7.2 -> 3.7.4

Semi-automatic update generated by
https://github.com/ryantm/nixpkgs-update tools. This update was made
based on information from
https://repology.org/metapackage/python3.7-typing_extensions/versions

pkgs/development/python-modules/typing-extensions/default.nix

···
 
 in buildPythonPackage rec {
   pname = "typing_extensions";
-  version = "3.7.2";
+  version = "3.7.4";
 
   src = fetchPypi {
     inherit pname version;
-    sha256 = "0wfsv71pvkyf2na938l579jh0v3kzl6g744ijgnahcwd4d9x0b7v";
+    sha256 = "15bx773a5zkk4hkwjl8nb5f8y5741vyyqb9q3jac6kxm1frk5mif";
   };
 
   checkInputs = lib.optional (pythonOlder "3.5") typing;